1. Field of the Invention
This invention relates generally to improvements in syringe and reservoir interfaces for use in infusion pumps such as those used for controlled delivery of medication to a patient. More specifically, this invention relates to an improved connection interface between a reservoir or syringe, infusion set tubing, and an infusion pump.
2. Description of the Related Art
Infusion pump devices and systems are relatively well-known in the medical arts, for use in delivering or dispensing a prescribed medication such as insulin to a patient. In one form, such devices comprise a relatively compact pump housing adapted to receive a syringe or reservoir carrying a prescribed medication for administration to the patient through infusion tubing and an associated catheter.
The infusion pump includes a small drive motor connected via a lead screw assembly for motor-driven advancement of a reservoir piston to administer the medication to the user. Programmable controls are normally provided for operating the drive motor continuously or at periodic intervals to obtain a closely controlled and accurate delivery of the medication over an extended period of time. Such infusion pumps are utilized to administer insulin and other medications, with exemplary pump constructions being shown and described in U.S. Pat. Nos. 4,562,751; 4,678,408; 4,685,903; 5,080,653 and 5,097,122, which are incorporated by reference herein.
Infusion pumps of the general type described above have provided significant advantages and benefits with respect to accurate delivery of medication or other fluids over an extended period of time. The infusion pump can be designed to be relatively compact as well as water resistant, and may thus be adapted to be carried by the user, for example, by means of a belt clip. As a result, important medication can be delivered to the user with precision and in an automated manner, without significant restriction on the user""s mobility or life-style, including the ability to participate in water sports.
Infusion sets refer to the tubing and connection apparatus which provide a path for the medication to flow from the reservoir or syringe located in the pump to the user. The connectors for attaching the infusion set tubing to the reservoirs can take various forms. A luer connection is a commonly used connection method. Nevertheless, it remains desirable to develop improved designs of connection methods to facilitate infusion procedures and to provide suitable interface connections which are water resistant so as to permit a user to participate in water sports.
An apparatus for connecting a reservoir having a septum and a base to a conduit, such as infusion set tubing, is provided. In certain aspects of the present invention, the apparatus comprises a cap and a releasable coupler which is adapted to releasably couple the base to the cap in one of two positions. A piercing member, such as a needle, is coupled to the conduit. The needle is disposed in the cap in a position other than the interior of the reservoir when the base is in the first position. The needle is further disposed to pierce the reservoir septum when the base is in the second position.
In another embodiment, the apparatus is used for connecting a reservoir having a septum and a base to a housing as well as to a conduit. The housing has a housing engagement member, such as a thread. The apparatus comprises a cap and a releasable coupler which is adapted to releasably couple the base to the cap in one of two positions. A piercing member, such as a needle, is releasably coupled to the conduit. The needle is disposed in the cap in a position other than the interior of the reservoir when the base is in the first position. The needle is further disposed to pierce the reservoir septum when the base is in the second position. The cap further includes an engagement member, such as a thread, which is adapted to engage with the housing engagement member.
In another embodiment, the cap further includes a vent port which is covered with hydrophobic material. This permits air to pass through the cap while preventing water from doing so.